Not quite time to stop testing aspirin response yet?

Neurointerventionalists have broadly adopted dual antiplatelet treatment (DAPT) strategies from cardiologists owing to the lack of high-level evidence in the neuroendovascular field.1 2 A pooled analysis on flow diversion treatment using DAPT estimated an overall risk of thromboembolic and hemorrhagic complications of 7% (95% CI 6% to 9%) and 5% (95% CI 4% to 6%), respectively.3 Surveys on DAPT strategies across major academic neurovascular centers in the USA demonstrated significant variation in the choice of antiplatelet regimen, the duration of administration of antiplatelet drugs, employment of platelet function testing, and the choice and duration of alternate antiplatelet therapy for hypo-responders and non-responders to clopidogrel.4 5 Recently, a randomized trial underpinned the value of antiplatelet therapy guided by platelet function monitoring to reduce thromboembolic complications in patients undergoing intracranial stent placement for cerebral aneurysms.6 We read the article ‘Effect of body weight on VerifyNow Aspirin platelet function test: a retrospective review’ by Sandler et al with great interest.7 Briefly, the authors analyzed VerifyNow assay results in 142 patients who had undergone neuroendovascular stent placement. Most patients were Caucasian (80.3%), non-obese (body mass index <30 in 64.8%), and received an aspirin dose of 300–325 mg (88.7%) with clopidogrel (94.4%) as the concomitant P2Y12 inhibitor. According to the authors’ institutional protocol, dual antiplatelet therapy was initiated 5–7 days before the intervention in elective cases. A total of 83.8% of patients achieved an initial therapeutic VerifyNow Aspirin assay result (aspirin reaction units (ARU) <550) and 86.2% (119/138) an initial therapeutic VerifyNow P2Y12 assay (P2Y12 reaction units (PRU) <215). Thus, the authors concluded that body weight did not influence the likelihood of obtaining a therapeutic VerifyNow Aspirin result and, perhaps more broadly, the clinical usefulness of …